When To Use As Or Like

[ISASIR]

Please I would like to know when I can use "as" or "like" because I really have a lot of problems trying to understand the difference and I actually do not get it, so please help me out but it´s useless to take a quiz if I do not know the explanation. thanks a lot

[naomimalan]

Strictly speaking, you should respect the following distinctions:

Like is a preposition. It is followed by a noun, a pronoun or a gerund, for example
You look like your sister/ She looks like you/ Having a dog is a bit like having a small child

As is a conjunction. It is followed by a clause with a subject and verb, for example
We've adopted a dog, as I told you.

As is also used before prepositional expressions, for example:
In South Africa, they drive on the left-hand side of the road, as in Europe.

However, more and more, people are using like instead of as, for example
We've adopted a dog, like I told you
...they drive on the left-hand side of the road, like in Europe.

But this is still considered incorrect in formal English.

[marciobarbalho]

[Not a teacher]

Get it from examples:

1) Bill works like an engineer. <-- Bill is not an engineer, he just works like one.
2) John works as a doctor. <-- John is a doctor.

Of course, there are lots of different cases. You could get it from reading/listening. Then you will be able to talk/write it instantaneously, without thinking.